Everything looks great on camera, except when you turn on smooth shading
Your face is made of a huge ngon, if the ngon is not completely flat it tends to creates artifacts like the ones we see when you smooth, because of the stretched triangles that compose it. So you need to correct the topology and work with quads as much as possible, sometimes tris... ngons are ok if they don't cause any problem.
For iphones see answers here and here for example.